1 files changed, 257 insertions, 0 deletions

diff --git a/arch/powerpc/platforms/iseries/htab.c b/arch/powerpc/platforms/iseries/htab.c
new file mode 100644
index 00000000000..3ae66ab9d5e
--- /dev/null
+++ b/arch/powerpc/platforms/iseries/htab.c
@@ -0,0 +1,257 @@
+/*
+ * iSeries hashtable management.
+ *      Derived from pSeries_htab.c
+ *
+ * SMP scalability work:
+ *    Copyright (C) 2001 Anton Blanchard <anton@au.ibm.com>, IBM
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+#include <asm/machdep.h>
+#include <asm/pgtable.h>
+#include <asm/mmu.h>
+#include <asm/mmu_context.h>
+#include <asm/abs_addr.h>
+#include <linux/spinlock.h>
+
+#include "call_hpt.h"
+
+static spinlock_t iSeries_hlocks[64] __cacheline_aligned_in_smp;
+
+/*
+ * Very primitive algorithm for picking up a lock
+ */
+static inline void iSeries_hlock(unsigned long slot)
+{
+        if (slot & 0x8)
+                slot = ~slot;
+        spin_lock(&iSeries_hlocks[(slot >> 4) & 0x3f]);
+}
+
+static inline void iSeries_hunlock(unsigned long slot)
+{
+        if (slot & 0x8)
+                slot = ~slot;
+        spin_unlock(&iSeries_hlocks[(slot >> 4) & 0x3f]);
+}
+
+static long iSeries_hpte_insert(unsigned long hpte_group, unsigned long va,
+                         unsigned long pa, unsigned long rflags,
+                         unsigned long vflags, int psize, int ssize)
+{
+        long slot;
+        struct hash_pte lhpte;
+        int secondary = 0;
+
+        BUG_ON(psize != MMU_PAGE_4K);
+
+        /*
+         * The hypervisor tries both primary and secondary.
+         * If we are being called to insert in the secondary,
+         * it means we have already tried both primary and secondary,
+         * so we return failure immediately.
+         */
+        if (vflags & HPTE_V_SECONDARY)
+                return -1;
+
+        iSeries_hlock(hpte_group);
+
+        slot = HvCallHpt_findValid(&lhpte, va >> HW_PAGE_SHIFT);
+        if (unlikely(lhpte.v & HPTE_V_VALID)) {
+                if (vflags & HPTE_V_BOLTED) {
+                        HvCallHpt_setSwBits(slot, 0x10, 0);
+                        HvCallHpt_setPp(slot, PP_RWXX);
+                        iSeries_hunlock(hpte_group);
+                        if (slot < 0)
+                                return 0x8 | (slot & 7);
+                        else
+                                return slot & 7;
+                }
+                BUG();
+        }
+
+        if (slot == -1) { /* No available entry found in either group */
+                iSeries_hunlock(hpte_group);
+                return -1;
+        }
+
+        if (slot < 0) {         /* MSB set means secondary group */
+                vflags |= HPTE_V_SECONDARY;
+                secondary = 1;
+                slot &= 0x7fffffffffffffff;
+        }
+
+
+        lhpte.v = hpte_encode_v(va, MMU_PAGE_4K, MMU_SEGSIZE_256M) |
+                vflags | HPTE_V_VALID;
+        lhpte.r = hpte_encode_r(phys_to_abs(pa), MMU_PAGE_4K) | rflags;
+
+        /* Now fill in the actual HPTE */
+        HvCallHpt_addValidate(slot, secondary, &lhpte);
+
+        iSeries_hunlock(hpte_group);
+
+        return (secondary << 3) | (slot & 7);
+}
+
+static unsigned long iSeries_hpte_getword0(unsigned long slot)
+{
+        struct hash_pte hpte;
+
+        HvCallHpt_get(&hpte, slot);
+        return hpte.v;
+}
+
+static long iSeries_hpte_remove(unsigned long hpte_group)
+{
+        unsigned long slot_offset;
+        int i;
+        unsigned long hpte_v;
+
+        /* Pick a random slot to start at */
+        slot_offset = mftb() & 0x7;
+
+        iSeries_hlock(hpte_group);
+
+        for (i = 0; i < HPTES_PER_GROUP; i++) {
+                hpte_v = iSeries_hpte_getword0(hpte_group + slot_offset);
+
+                if (! (hpte_v & HPTE_V_BOLTED)) {
+                        HvCallHpt_invalidateSetSwBitsGet(hpte_group +
+                                                         slot_offset, 0, 0);
+                        iSeries_hunlock(hpte_group);
+                        return i;
+                }
+
+                slot_offset++;
+                slot_offset &= 0x7;
+        }
+
+        iSeries_hunlock(hpte_group);
+
+        return -1;
+}
+
+/*
+ * The HyperVisor expects the "flags" argument in this form:
+ *      bits  0..59 : reserved
+ *      bit      60 : N
+ *      bits 61..63 : PP2,PP1,PP0
+ */
+static long iSeries_hpte_updatepp(unsigned long slot, unsigned long newpp,
+                        unsigned long va, int psize, int ssize, int local)
+{
+        struct hash_pte hpte;
+        unsigned long want_v;
+
+        iSeries_hlock(slot);
+
+        HvCallHpt_get(&hpte, slot);
+        want_v = hpte_encode_v(va, MMU_PAGE_4K, MMU_SEGSIZE_256M);
+
+        if (HPTE_V_COMPARE(hpte.v, want_v) && (hpte.v & HPTE_V_VALID)) {
+                /*
+                 * Hypervisor expects bits as NPPP, which is
+                 * different from how they are mapped in our PP.
+                 */
+                HvCallHpt_setPp(slot, (newpp & 0x3) | ((newpp & 0x4) << 1));
+                iSeries_hunlock(slot);
+                return 0;
+        }
+        iSeries_hunlock(slot);
+
+        return -1;
+}
+
+/*
+ * Functions used to find the PTE for a particular virtual address.
+ * Only used during boot when bolting pages.
+ *
+ * Input : vpn      : virtual page number
+ * Output: PTE index within the page table of the entry
+ *         -1 on failure
+ */
+static long iSeries_hpte_find(unsigned long vpn)
+{
+        struct hash_pte hpte;
+        long slot;
+
+        /*
+         * The HvCallHpt_findValid interface is as follows:
+         * 0xffffffffffffffff : No entry found.
+         * 0x00000000xxxxxxxx : Entry found in primary group, slot x
+         * 0x80000000xxxxxxxx : Entry found in secondary group, slot x
+         */
+        slot = HvCallHpt_findValid(&hpte, vpn);
+        if (hpte.v & HPTE_V_VALID) {
+                if (slot < 0) {
+                        slot &= 0x7fffffffffffffff;
+                        slot = -slot;
+                }
+        } else
+                slot = -1;
+        return slot;
+}
+
+/*
+ * Update the page protection bits. Intended to be used to create
+ * guard pages for kernel data structures on pages which are bolted
+ * in the HPT. Assumes pages being operated on will not be stolen.
+ * Does not work on large pages.
+ *
+ * No need to lock here because we should be the only user.
+ */
+static void iSeries_hpte_updateboltedpp(unsigned long newpp, unsigned long ea,
+                                        int psize, int ssize)
+{
+        unsigned long vsid,va,vpn;
+        long slot;
+
+        BUG_ON(psize != MMU_PAGE_4K);
+
+        vsid = get_kernel_vsid(ea, MMU_SEGSIZE_256M);
+        va = (vsid << 28) | (ea & 0x0fffffff);
+        vpn = va >> HW_PAGE_SHIFT;
+        slot = iSeries_hpte_find(vpn);
+        if (slot == -1)
+                panic("updateboltedpp: Could not find page to bolt\n");
+        HvCallHpt_setPp(slot, newpp);
+}
+
+static void iSeries_hpte_invalidate(unsigned long slot, unsigned long va,
+                                    int psize, int ssize, int local)
+{
+        unsigned long hpte_v;
+        unsigned long avpn = va >> 23;
+        unsigned long flags;
+
+        local_irq_save(flags);
+
+        iSeries_hlock(slot);
+
+        hpte_v = iSeries_hpte_getword0(slot);
+
+        if ((HPTE_V_AVPN_VAL(hpte_v) == avpn) && (hpte_v & HPTE_V_VALID))
+                HvCallHpt_invalidateSetSwBitsGet(slot, 0, 0);
+
+        iSeries_hunlock(slot);
+
+        local_irq_restore(flags);
+}
+
+void __init hpte_init_iSeries(void)
+{
+        int i;
+
+        for (i = 0; i < ARRAY_SIZE(iSeries_hlocks); i++)
+                spin_lock_init(&iSeries_hlocks[i]);
+
+        ppc_md.hpte_invalidate  = iSeries_hpte_invalidate;
+        ppc_md.hpte_updatepp    = iSeries_hpte_updatepp;
+        ppc_md.hpte_updateboltedpp = iSeries_hpte_updateboltedpp;
+        ppc_md.hpte_insert      = iSeries_hpte_insert;
+        ppc_md.hpte_remove      = iSeries_hpte_remove;
+}